diff --git a/fire/decorators.py b/fire/decorators.py
index 9e56d6df..b2e9b322 100644
--- a/fire/decorators.py
+++ b/fire/decorators.py
@@ -111,5 +111,5 @@ def GetMetadata(fn):
 def GetParseFns(fn):
   # type: (...) -> dict
   metadata = GetMetadata(fn)
-  default = dict(default=None, positional=[], named={})
+  default = {"default": None, "positional": [], "named": {}}
   return metadata.get(FIRE_PARSE_FNS, default)